// Copyright (C) Kumo inc. and its affiliates.
// Author: Jeff.li lijippy@163.com
// All rights reserved.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
//

package system

import (
	"bytes"
	"path"
	"text/template"

	"github.com/kumose/kmopt/embed"
	"github.com/kumose/kmopt/pkg/utils"
)

// Config represent the data to generate systemd config
type Config struct {
	ServiceName         string
	User                string
	MemoryLimit         string
	CPUQuota            string
	IOReadBandwidthMax  string
	IOWriteBandwidthMax string
	LimitCORE           string
	DeployDir           string
	DisableSendSigkill  bool
	TimeoutStopSec      string
	TimeoutStartSec     string
	GrantCapNetRaw      bool
	// Takes one of no, on-success, on-failure, on-abnormal, on-watchdog, on-abort, or always.
	// The Template set as always if this is not set.
	Restart     string
	SystemdMode string
}

// NewConfig returns a Config with given arguments
func NewConfig(service, user, deployDir string) *Config {
	return &Config{
		ServiceName: service,
		User:        user,
		DeployDir:   deployDir,
	}
}

// WithMemoryLimit set the MemoryLimit field of Config
func (c *Config) WithMemoryLimit(mem string) *Config {
	c.MemoryLimit = mem
	return c
}

// WithCPUQuota set the CPUQuota field of Config
func (c *Config) WithCPUQuota(cpu string) *Config {
	c.CPUQuota = cpu
	return c
}

// WithIOReadBandwidthMax set the IOReadBandwidthMax field of Config
func (c *Config) WithIOReadBandwidthMax(io string) *Config {
	c.IOReadBandwidthMax = io
	return c
}

// WithIOWriteBandwidthMax set the IOWriteBandwidthMax field of Config
func (c *Config) WithIOWriteBandwidthMax(io string) *Config {
	c.IOWriteBandwidthMax = io
	return c
}

// WithLimitCORE set the LimitCORE field of Config
func (c *Config) WithLimitCORE(core string) *Config {
	c.LimitCORE = core
	return c
}

// WithSystemdMode set the SystemdMode field of Config
func (c *Config) WithSystemdMode(mode string) *Config {
	c.SystemdMode = mode
	return c
}

// WithTimeoutStopSec set the TimeoutStopSec field of Config
func (c *Config) WithTimeoutStopSec(sec string) *Config {
	c.TimeoutStopSec = sec
	return c
}

// WithTimeoutStartSec set the TimeoutStartSec field of Config
func (c *Config) WithTimeoutStartSec(sec string) *Config {
	c.TimeoutStartSec = sec
	return c
}

// ConfigToFile write config content to specific path
func (c *Config) ConfigToFile(file string) error {
	config, err := c.Config()
	if err != nil {
		return err
	}
	return utils.WriteFile(file, config, 0755)
}

// Config generate the config file data.
func (c *Config) Config() ([]byte, error) {
	fp := path.Join("templates", "systemd", "system.service.tpl")
	tpl, err := embed.ReadTemplate(fp)
	if err != nil {
		return nil, err
	}
	return c.ConfigWithTemplate(string(tpl))
}

// ConfigWithTemplate generate the system config content by tpl
func (c *Config) ConfigWithTemplate(tpl string) ([]byte, error) {
	tmpl, err := template.New("system").Parse(tpl)
	if err != nil {
		return nil, err
	}

	content := bytes.NewBufferString("")
	if err := tmpl.Execute(content, c); err != nil {
		return nil, err
	}

	return content.Bytes(), nil
}
